1. Field of the Invention
The present invention relates to a method for producing a substrate having dispersed particles of a dendrimer compound on the surface thereof, and a substrate having dispersed particles of a dendrimer compound on the surface thereof.
2. Related Art
In recent years, metal nanoparticles have attracted attention as basic materials for use in medical drugs, electronically functional materials, environmentally compatible materials and the like. Nanoparticles are fine particles having a diameter of typically no greater than 10 nm, and they are not only useful per se as medical drugs, electronic function materials, environmentally compatible materials and the like, but also superior in activities as a catalyst for synthesizing the same. Such characteristic features result from a quantum effect due to the nanoparticles being fine particles having a diameter of no greater than 10 nm, and a greater active surface area accompanied by being fine particles. However, micronization of a metal is difficult, in general, since an agglutinative action among the particles increases along with the extent of micronization.
Under such circumstances, as methods for producing nanoparticles, methods in which a dendrimer compound is used as a template have been proposed (see, for example, Patent Document 1). Dendrimer compounds that include in the backbone a nitrogen atom, etc., having an unpaired electron pair are capable of forming a complex with a Lewis acid, and can incorporate a variety of molecules and atoms within their molecules.
Patent Document 2 has proposed production of metal nanoparticles utilizing such characteristic features of a dendrimer compound, and the production includes forming a complex by allowing all imine moieties of a phenyl azomethine dendrimer compound to be coordinated with a metal compound such as rhodium first, and thereafter reducing the metal compound included in the complex in a solution. According to this method, metal nanoparticles are stabilized within the phenyl azomethine dendrimer; therefore, a decrease in activity such as a catalytic action accompanied by aggregation of metal nanoparticles can be prevented.    Patent Document 1: Japanese Unexamined Patent Application (Translation of PCT Publication), Publication No. 2001-508484    Patent Document 2: Japanese Unexamined Patent Application, Publication No. 2008-100987    Non-Patent Document 1: M. Higuchi, S. Shiki, K. Ariga, K. Yamamoto, J. Am. Chem. Soc., 2001, 123, 4414-4420    Non-Patent Document 2: K. Yamamoto, T. Imaoka, W.-J. Chun, O. Enoki, H. Katoh, M. Takenaga, A. Sonoi, Nature Chem., 2009, 1, 397-402    Non-Patent Document 3: N. Satoh, T. Nakashima, K. Kamikura, K. Yamamoto, Nature Nanotech, 2008, 3, 106-111    Non-Patent Document 4: I. Nakamula, Y. Yamanoi, T. Imaoka, K. Yamamoto, H. Nishihara, Angew. Chem., Int. Ed., 2011, 50, 5830-5833    Non-Patent Document 5: D. Liu, H. Zhang, P. C. M. Grim, S. DeFeyter, U.-M. Wiesler, A. J. Berresheim, K. Mullen, and F. C. DeSchryver, Langmuir, 2002, 18, 2385-2391    Non-Patent Document 6: M. Sano, J. Okamura, A. Ikeda, and S. Shinkai, Langmuir. 2001, 17, 1807-1810